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Connecting with a large number of social groups online can increase stress levels, according to a new report.

As an individual increases the number of social circles they are linked to online, they become more likely to find social media a source of anxiety, experts found.

The study pointed to "social landmines" which can arise when people become online friends with conflicting social spheres, such as their boss and parents as well as their usual friendship group.

The report was compiled by researchers from the University of Edinburgh Business School, who surveyed more than 300 Facebook users.

Those taking part in the study were mostly students with an average age of 21.

Researchers concluded that stress arises when a user presents a version of themselves on social media which would be deemed unacceptable by some of their online "friends", such as posts about swearing, drinking or smoking.

The more groups of people there are in an individual's collection of online friends, the greater the potential for causing offence.

In particular, adding employers or parents to the friendship list resulted in the greatest increase in anxiety levels.

The report said that 55% of parents follow their children on Facebook and more than half of employers claim to have not hired someone on the basis of their social networking page.

Researchers also noted that, on average, people are online friends with seven different social circles.

The most common group was friends known offline, followed by extended family and siblings. Friends of friends and colleagues were other groups people were likely to connect with online.

The report also found that more people are online friends with their former partners than with their current partners. Only 56% of users were pals with their boyfriend, girlfriend or spouse online, compared with 64% of exes.

A third of people used privacy settings to control the information seen by different types of friends on their profile.

Report author Ben Marder, an early career fellow in marketing at the business school, said: "Facebook used to be like a great party for all your friends where you can dance, drink and flirt.

"But now, with your mum, dad and boss there, the party becomes an anxious event full of potential social landmines."